A working machine, such as a dump truck, that hauls, as a cargo, ore, rocks or the like excavated at a mine or the like, as a cargo generally includes a body frame, front wheels and rear wheels rotatably provided on the body frame, a vessel tiltably mounted on the body frame for carrying a cargo, and front suspension cylinders and rear suspension cylinders disposed between the body frame and the front wheels and rear wheels, respectively, for reducing shocks to the vehicle body during traveling. The working machine of such configurations is provided with a load measuring apparatus that measures the load of the cargo carried on the vessel.
As one of conventional technologies on load measuring apparatuses of this type for working machines, a load measuring apparatus is known. This load measuring apparatus is provided with a processing unit, which receives cylinder pressures of front suspension cylinders and rear suspension cylinders from pressure sensors and computes the load of a cargo carried on a vessel (see, for example, Patent Document 1 to be described below).
The load measuring apparatus of the conventional technology includes rear-wheel speed detectors that detect speeds of left and right, rear wheels on a body, a speed difference detector that detects a difference between the speeds from the respective rear-wheel speed detectors, and a final cargo load confirmation device having a final confirmation arithmetic unit that outputs, as a final cargo load, a cargo load computed by the processing unit when the difference between the speeds of the respective rear wheels from the speed difference detector has reached below a preset value or that disables the cargo load, which has been computed by the processing unit, as a final out put of cargo load when the difference between the speeds of the respective rear wheels from the speed difference detector has exceeded the preset value.